I'm ready to take a big $15K gulp and launch my order for a 74" composite Hartzell and associated spinner for my 7A to replace the Sensenich aluminum FP now installed. Superior XP-IO-360-B1A2. Would love first to hear of any experience out there with this specific swap- anybody? Thanks!

Follow on from Hartstoc's question
I am also interested in understanding the advantages of a 74" Hartzell Composite prop at $13000 against a constant speed at half the price. What makes this prop so special and why is it offered by Vans. I'm keen to hear from someone with experience as I am also about to install a 74" Composite on a 7A

Wow, Can't believe there hasn't been any response to this post!
Surely someone has this combination!?

I’ve concluded that there must be very few RV’s actually flying this prop and I’m pretty sure the price point is the reason- it just doesn’t quite pass most builder’s intuitive cost-benefit analysis and I totally appreciate that point of view. Advantages over the aluminum blades is probably going to be somewhat marginal, but there should be quite a few of them, so I did place my order and my prop/spinner ships in about a week.

I’m pretty fanatical about weight, especially right at the nose-station, so the 12 pounds saved there means a lot to me. I’m deleting the belt-driven alternator and going with a spline-driven B&C as primary for much the same reason. Any reduction in polar mass makes for a more nimble aerobat. Significantly less gyroscopic inertia will also contribute to maneuverability.

The working blade section on the composite carries much closer to the root because structural issues dictate that that aluminum blades grow so fat there that little thrust, much drag, and considerable turbulance is produced in the region just ahead of the cooling inlets. Both thrust in T.O./climb and pumping action into the cooling inlets should be improved. More sustained high-performance climbs without dangerous CHT levels should be possible- we’ll see. By all accounts I have heard, static thrust is dramatically better with the composite.

The absence of any restricted zones of sustained RPM for the composite blades is also a plus- just one less thing to pay attention to.

Is all this worth a $5K+ premuim? I hope the answer is yes for me, but I don’t expect that it would be for everyone.

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